Upon unloading in a forming process there is elastic recovery, which is the release of the elastic strainsudand the redistribution of the residual stresses through the thickness direction. It causes changes in shapeudand dimensions that can create major problem in the external appearance of outer panels. Thus surfaceuddeflection prediction is an important issue in sheet metal forming industry. The shape and dimensionudproblem in press forming is defined as a trouble mainly caused by the elastic recovery of materials afterudforming. The use of high strength steel sheets in the manufacturing of automobile outer panels hasudincreased in the automotive industry over the years because of its lightweight and fuel-efficientudimprovement. But one of the major concerns of stamping is surface deflection in the formed outerudpanels. Hence, to be cost effective, accurate prediction must be made of its formability. The automotiveudindustry places rigid constraints on final shape and dimensional tolerances as well as externaludappearance quality of outer panels.udKeywords: Surface deflection, automotive outer
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